Featured Research

from universities, journals, and other organizations

Stanford Researchers Eye New Chip's Potential As An Artificial Retina

Date:
June 22, 2004
Source:
Stanford University Medical Center
Summary:
Researchers at the Stanford University School of Medicine have developed a prototype for a new kind of implantable chip they believe could be adapted to serve as both a prosthetic retina for people who suffer from a common form of age-related blindness and as a drug-delivery system that could treat conditions such as Parkinson's disease.

STANFORD, Calif. -- Researchers at the Stanford University School of Medicine have developed a prototype for a new kind of implantable chip they believe could be adapted to serve as both a prosthetic retina for people who suffer from a common form of age-related blindness and as a drug-delivery system that could treat conditions such as Parkinson's disease.

Related Articles


Where other types of chips use electricity to stimulate nerves, this one instead tickles cells with minute amounts of chemicals. Because nerve cells normally communicate with each other by releasing chemicals known as neurotransmitters, the new device points to a more effective way of treating very delicate tissues, such as those in the eye and in the brain.

"People believed that a neurotransmitter device could not be done, in the sense that it wasn't possible to deliver such small volumes of chemicals, but we show that it is possible and that further research along these lines should be done," said Harvey A. Fishman, MD, PhD, director of the Stanford Ophthalmic Tissue Engineering Laboratory, who led the study. Fishman and his interdisciplinary team of colleagues report their findings in this week's advance online issue of Proceedings of the National Academy of Sciences.

The team built a computer chip with four tiny openings, and used it to control the environment of neuron-like cells. The chip exuded droplets of chemicals using electro-osmosis. They then gauged the cells' responses using fluorescent dye. The chip also withdraws fluid when needed, which could prevent a potentially toxic buildup of the chemicals.

"We're very excited about the possibilities that are now available," said Mark Blumenkranz, MD, professor and chair of the Department of Ophthalmology and a co-author of the study. The chip "may allow for graded responses to activation," he added, enabling a more complex range of signals than the simple on/off capabilities of electrical devices.

Although the chip has many potential applications, both in medicine and research, the team is mainly concerned with devising a treatment for age-related macular degeneration, a condition that is the most common cause of blindness. In a healthy eye, vision occurs when light-sensitive cells in the retina convert light into electrical signals that the optic nerve then transmits to the brain. These cells receive nutrients and excrete waste through a thin layer of cells that covers them. In age-related macular degeneration, this life-giving layer degrades over time, leading to the eventual death of the cells beneath.

Patients with the disease typically lose central vision. In about 80 percent of those patients, some underlying cells remain alive although the cover layer has degraded, and they could potentially be treated with tissue transplants. For the remaining 20 percent of patients, however, a chip implanted on the retina could prove to be the best option. Rather than just four openings, such a chip would have thousands, each filling in for a lost light-sensitive cell that could then relay visual signals to the brain.

"It's almost like an ink-jet printer for the eye," Fishman said.

Because the chip can draw droplets of fluid in as well as out, it could also enable researchers to take samples in real time, giving them a chemical picture of what goes on in living tissues during certain processes. And it could deliver small amounts of drugs precisely where they're needed, such as dopamine in the brains of patients with Parkinson's disease. "It's a very new way to interface with the brain," Fishman said.

However, he estimated the device is still several years away from clinical trials. "We still have to look at how these chips interact with the body and ensure there's no toxicity or clogging of microchannels and so forth," he said. "There are a lot of potential pitfalls, as with any new technology, but the advantages are well worth the potential challenges."

###

Other Stanford collaborators on the study were Mark Peterman, PhD, a former graduate student in applied physics, and Jaan Noolandi, PhD, senior research scientist in ophthalmology. Funding came from VISX Inc., a California-based company that specializes in the design, manufacture and marketing of proprietary laser vision-correction technologies.

Stanford University Medical Center integrates research, medical education and patient care at its three institutions - Stanford University School of Medicine, Stanford Hospital & Clinics and Lucile Packard Children's Hospital at Stanford. For more information, please visit the Web site of the medical center's Office of Communication & Public Affairs at http://mednews.stanford.edu.


Story Source:

The above story is based on materials provided by Stanford University Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

Stanford University Medical Center. "Stanford Researchers Eye New Chip's Potential As An Artificial Retina." ScienceDaily. ScienceDaily, 22 June 2004. <www.sciencedaily.com/releases/2004/06/040622012701.htm>.
Stanford University Medical Center. (2004, June 22). Stanford Researchers Eye New Chip's Potential As An Artificial Retina. ScienceDaily. Retrieved November 28, 2014 from www.sciencedaily.com/releases/2004/06/040622012701.htm
Stanford University Medical Center. "Stanford Researchers Eye New Chip's Potential As An Artificial Retina." ScienceDaily. www.sciencedaily.com/releases/2004/06/040622012701.htm (accessed November 28, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, November 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rural India's Low-Cost Sanitary Pad Revolution

Rural India's Low-Cost Sanitary Pad Revolution

AFP (Nov. 28, 2014) — One man hopes his invention -– a machine that produces cheap sanitary pads –- will help empower Indian women. Duration: 01:51 Video provided by AFP
Powered by NewsLook.com
Research on Bats Could Help Develop Drugs Against Ebola

Research on Bats Could Help Develop Drugs Against Ebola

AFP (Nov. 28, 2014) — In Africa's only biosafety level 4 laboratory, scientists have been carrying out experiments on bats to understand how virus like Ebola are being transmitted, and how some of them resist to it. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
Ebola Leaves Orphans Alone in Sierra Leone

Ebola Leaves Orphans Alone in Sierra Leone

AFP (Nov. 27, 2014) — The Ebola epidemic sweeping Sierra Leone is having a profound effect on the country's children, many of whom have been left without any family members to support them. Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
Experimental Ebola Vaccine Shows Promise In Human Trial

Experimental Ebola Vaccine Shows Promise In Human Trial

Newsy (Nov. 27, 2014) — A recent test of a prototype Ebola vaccine generated an immune response to the disease in subjects. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins